Internet Protocol (IP) Multimedia Subsystem (IMS) provides a framework for offering real-time, person-to-person communication services that combine the best aspects of switched networks (telephony) and packet networks (IP). IMS integrates speech and video telephony with digital services such as telemetry, telecommand, text messaging, etc.
Due to the vast array of protocols and media that will be handled by IMS, open and extensible protocols are needed define parameters used for various IMS services such as transport methods, stream and data formats, and directory services. One such protocol is Session Initiation Protocol (SIP). As defined in RFC3261, SIP is “an application-layer control (signaling) protocol for creating, modifying, and terminating sessions with one or more participants. These sessions include Internet telephone calls, multimedia distribution, and multimedia conferences.”
When establishing multimedia conferences, there are a number of communication channels that must be established using different protocols. One such channel is known as “floor control”. Floor control is the arbitration of control of the media and/or data streams. Since only one user should be speaking or controlling a cursor at any given time, the establishing and passing of floor control will require one of the communication channels be set up with all users.
Media signaling requires another communications channel. The floor control can therefore be considered as a side channel, and the media signaling would be considered a main channel within the conference. The SIP provides a means for establishing channels such as media signaling, floor control, and other side channels that may be needed. These channels can be established through SIP methods such as “PUBLISH” for floor control and “INVITE” for media signaling. Other new SIP methods could also be proposed for these purposes.
Another aspect of multimedia conferences is group management. Group management involves, among other things, establishing the users who are invited to the conference and establishing privileges of users.
What is needed in the art is a way to perform group management in IMS conference services. Further needed is a system that utilizes available protocols that are open and extensible. The present invention fulfills these and other needs, and addresses other deficiencies of prior art implementations.